Process of producing a resinous compound.



35 time to ascertain the oxygen content, as for QTATES Para EORRIS WHIPPLE, NEW YORK, N. Y., ASSIGNOE TO'STANDARD CHEMICAL COMPANY,

OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

PROCESS OF PRODUCING A RESINOUS COMJ EOUND.

No Drawing.-

Specification of i'ietters Ila-tent. Application filed November 6, 1909. Serial No. 526,660.

Patented Dec. 30, 1913.

To all whom it may concern:

, citizen of the United States, residing, at

New York in the county of New York and State of New York, have invented new and useful Improvements in Processes of Producing a NewResinous Compound, (Case A,) of which the following is a specification.

This invention, relates to the processof producing a new resinous compound, the productbeing in the form of a soft, nonoxidizing, non-drying, permanently plastic mass of very high specific electrical re-- sista'nce factor, which properties admirably adapt the same to the insulationof electrical cables and the like, and to various other uses, said product forming the basis of my co-pending application, Serial No. 526,661, filed of even date herewith.

In carrying out the process any resin which consists essentially of abietic anhydrid or abietic acid, preferably rosin, 1s placed in an iron still and heated to a temperature of approximately 135 C., which has the effect, of course, of melting the rosin. While therosin is still in molt-en condition, and not overheated, moist airis forced through the molten mass for the purpose of oxidizing the abietic acid of the rosin, and until the contents of the still shows a .high percentage of what is apparently'tetra-oxyabietic acid. This time will, of course,-:'

probably vary with each particular batch of rosin treated, and can be regulated and determined by testing samples from timeto example by treating a chloroform solution 'of the compound with iodin solution and titrating back' the uncombined iodin, the proportion of iodin consumed giving the percentage of rosin still left unchanged, or by subjecting the selected specimens to electrical voltage or puncture tests; the conditions of the latter being that two hemispherical poles say 1 c. m. in diameter placed one tenth inch apart with a portion of the specimens filling the gap will require atleast, 20,000 volts to show a puncture of the specimen; or, inthe alternative twenty sheets of pure Manila paper, each six mils. gage, and previously saturated with the material, are placed between fiat disks and compressed to a working distance of about one tenth inch and placed between the terminals of a generator will not be ruptured or punctured at a voltage less than 30,000

calculated on the mean square reading of a Thomson voltmeter.

The chemical changes which take place in the foregoing process cannot be definitely specified, but probably consist in the formation, from abietic anhydrid and abietic acid, of tetra-oxyabietic acid, or more properly, tetra-oxyabietin, by the combined action of the moisture and the oxygen introduced with the moist air, with the further possibility of many subsidiary compounds being formed which are removed in the later oxidation process. I The oxidation of the abietic oxid and abietic anhydrid to produce the product cannot be effected by air alone or by steam. alone but only by the conjoint action of the two. A further effect of treating the molten rosin, at the temperature indicated, with a blast of moist air is the elimination by oxidation, of all the turpentine products and organic acids which may have been present as impurities in the original rosin.

After the foregoing operation has been conducted for the necessary period of time, as. determined by the tests aforesaid, the compound in the still is preferably heated to a temperature of approximately 140 C. and dry air is passed through the same, for the purposes for which it is intended. Too high temperature will be evidenced by the coming over of comparatively large volumes of turpentine vapors, and as all such products in the original rosin were eliminated by the first steps of the process, their presence during the second stage of the operation indicates their formation at the expense of the products resulting from the first step. Re-

sulting from the last step mentioned is the final product, which may be best defined by its peculiar physical characteristics and' also by comparison with the rosin from which it is derived. The product is a soft gummy I material, having a specific gravity of ap- .As is well known, rosin which constitutes.

the initial substance, is a transparent or translucent resin havin a faint turpentine odor, and shows a definite fracture when broken. The specific gravity of rosin is between 1.07 and 1.1, and it is, as is well understood soluble in alcohol, more or less soluble in petroleum spirits, is not soluble in petroleum oils, and on oxidation, either in the air or by artificial means, results in a pulverulent mass. The product of the herein described process is less soluble in petroleum spirits but is freely. soluble in petroleum oils. The composition of the resin acid in rosin is approximately abictic acid."

From the foregoing, the essential differences between the initial resin or rosin and the resulting product of the process, as described, are apparent. -The ultimate product may be further described as non-drying, incapable of further oxidation under any circumstances or conditions of ordinary use, an "retainsits soft plastic condition indefinitel it is free from carbonaceous particles and contains no rosin oil, no pinene derivatives and no volatile organic acids.

Although the product finds many useful .applications in the arts, its nonoxidizing and non-drying character, its erfect and permanent plasticity and its hlgh specific electrical resistance factor, to wit, lSXlO" mcgohms per cubic centimeter, which as compared with rosin is about one to five in favor of the product, render it essentially valuable as an insulating medium for electrical cables, and it is in this particular field that the. invention finds its widest application.

Whatl claim is:

1. The process of producing anew resinous compound, which consists in heating a resin in the presence of moisture to a temperature suflicient to break up the complex turpentine products and volatilize the same together withthe volatile organic'acids', in-

creasingthe temperature and passlng dryair through the molten mass.- 3. The process of producing a new resinous compound, which consists in heating moist resin to a temperature of approxi- "mately 135 0., increasing the temperature and subjecting the mass to the action of an oxidizing agent.

4. The process of producing a new resinous compound which consists in heating a resin to a temperature of approximately- 135 0., passing moist air through the'molten mass, heating the residue to approximately atemperature of 140 C. and passing dry air through the mass.

The process of producing anew resinous compound which consists in heating a resin at a. temperature of approximately 135- C. in the'presence of moisture, increasing the ten'iperature and passing air through the mass.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

. DORE-IS WHIPPLE. Witnesses:

MERLE F. Sr. JoHN, I'IARRIETT Rnssn. 

